Mercerizing combined

Cellulose is insol in w, ale, eth all known simple org solvs. The best solv for it is cuprammonium hydroxide, [Cu(NH3)4(OH)2], also called Schweitzer s Reagent. It is also sol in a coned soln of Ca thiocyanate alone or in combination with formaldehyde. Other solvs gelatinizers for cellulose include zinc chloride (in 40% soln on heating), basic beryllium perchlorate, 84% phosphoric acid, selenic acid, arsenic acid, sulfurous acid, 66% HBr, 70-75% HF, coned HI, chloral with pyridine, chloral hydrate in H2S04, and inorg salts(such as NaCl) in coned solns at high temps. Coned solns of NaOH at ca -10° only partially dissolve cellulose while the remainder is swelled "mercerized . 

Some irmovative open width washing units are developed in which steam, water and air are projected onto both sides of fabric in any desired combination to generate turbulance and intensive washing of the mercerized fabrics. 

Based on the tubular fabric mercerizing machine, Domier, GmbH, has developed a combinable mercerizing and bleaching concept for tubular warp knitted fabrics. The combined mercerizing/bleaching machine (Fig. 9-23) comprises im-... 

Figure 9-23. Combined mercerizing/bleaching machine for tubular warp knitted fabrics (Courtesy of Domier, GmbH).

The animal fibers combine with most of the organic dyes. Cotton and other vegetable fibers cannot, in general, be dyed directly with the organic coloring matters except with certain so-called sulphur colors or with dyes derived from benzidine. Mercerized cotton, cellulose nitrates, and cellulose acetates can be dyed by substances which do not affect unaltered cellulose. 

It has been observed from the above discussion that mechanical, physico-chemical and fire retardancy properties of UPE matrix increases considerably on reinforcement with surface-modified natural cellulosic fibers. The benzoylated fibers-reinforced composite materials have been found to have the best mechanical and physico-chemical properties, followed by mercerized and raw Grewia optiva fibers-reinforced composites. From the above data it is also clear that polymer composites reinforced with 30% fibers loading showed the best mechanical properties. Further, benzoylated fibers-reinforced composites were also found to have better fire retardancy properties than mercerized and raw fibers-reinforced polymer composites. Fire retardancy behavior of raw and surface-modified Grewia optiva/GPE composites have been found to increase when fire retardants were used in combination with fibers. This increase in fire retardancy behavior of resulted composites was attributed to the higher thermal stability of magnesium hydroxide/zinc borate. 

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